Is TPM maul more powerful than bane?

What proves maul to be superior to bane?

depends. lucas made him to be superior to the previous sith back in 1999 (maybe not all sith, but mostly all), but things changed over time. bane changed and maul changed. now its up for anybody to guess which one of the two is stronger.

It can be argued Maul > Plaguies and Plaguies has massive scaling over bane so yeah

The power levels of characters in the Star Wars universe are often subjective and dependent on the story being told, and it's difficult to definitively say whether one character is more powerful than another. However, both Darth Maul and Darth Bane are considered to be some of the most powerful Sith Lords in the franchise's history.
Darth Maul is a character who first appeared in "The Phantom Menace" and was trained as a Sith Lord by Darth Sidious. He is known for his incredible physical prowess, acrobatic fighting style, and use of a double-bladed lightsaber. He also survived being cut in half by Obi-Wan Kenobi and went on to become a major player in the Clone Wars era of the franchise.
Darth Bane, on the other hand, is a character from the Star Wars Legends continuity, who is credited with creating the Rule of Two, a Sith philosophy that dictates that there can only be two Sith at a time: a master and an apprentice. Bane is known for his immense power in the dark side of the Force, as well as his strategic mind and cunning.
While both characters are incredibly powerful in their own ways, it's difficult to compare them directly. Darth Maul is known for his incredible physical abilities and combat skills, while Darth Bane is known for his mastery of the dark side of the Force and his cunning as a strategist. Ultimately, their relative power levels may depend on the specific story being told and the context in which they are portrayed.